JP2005209837A - Stage circulator and image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce a time required for the exposure preparation of a plurality of stages circulating in a circuit. <P>SOLUTION: In a stage member circulator 11 provided in a laser exposing device 10, while a stage member 20 (30) is elevated up, a loader 80 loads a substrate material 200. Further, while the stage member 20 (30) is dropped, an unloader unloads the substrate material 200. For this reason, a time of loading and unloading can be curtailed and a time required for the exposure preparation can be reduced. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention is a stage circulation device in which a plurality of stages on which a load is mounted by a loader and the load is lowered by an unloader is moved up and down to change the height and horizontally move and circulate at a height that can pass each other, The present invention also relates to an image forming apparatus that forms an image on a mounted object mounted on a stage circulation device.

  Conventionally, in an image exposure apparatus that forms an image by exposing an object mounted on a stage such as a printed circuit board, multiple stages are moved up and down between the upper and lower stages, and the height is changed between the upper and lower stages. A method is used in which exposure is performed continuously by moving horizontally and circulating so as to pass each other (see, for example, Patent Documents 1 and 2).

  In Patent Documents 1 and 2, since the stage is stopped and loaded and unloaded, much time is required for exposure preparation. For this reason, by the time the exposure of the substrate on the previous stage is completed, the exposure preparation for the next stage cannot be completed, and continuous exposure cannot be performed.

  If loading and unloading is performed at high speed, the exposure preparation time can be shortened. However, if loading and unloading is performed at high speed, the vibration applied to the stage increases, and this vibration propagates to the stage during exposure. The image may be blurred or misaligned.

Also, if the substrate is loaded onto the stage without applying a pressing force to the stage, the loading can be performed at a high speed, but there is a problem that the substrate cannot be warped and the substrate cannot be brought into close contact with the suction stage. It was.
Japanese Patent Application No. 2003-191116 Japanese Patent Application No. 2003-191118

  The present invention has been made in consideration of the above-mentioned facts, and while reducing the time required for preparation for exposure and the like, a necessary pressing force sufficient to bring the substrate into close contact with the stage is applied to the mounted object and the stage, and then the stage. The purpose is to reduce the vibration applied to the.

  The stage circulating apparatus according to claim 1 is configured such that a plurality of stages on which a load is mounted by a loader and the load is lowered by an unloader move up and down to change the height and move horizontally at a height at which they can pass each other. The stage loader circulates in such a manner that the loader mounts the load on the stage while the stage is moving up and down.

  In the stage circulating apparatus according to the first aspect, the plurality of stages are loaded with the load by the loader, and the load is lowered by the unloader. The plurality of stages move up and down to change their height, move horizontally and circulate at a height at which they can pass each other.

  Here, the loader mounts the load on the stage while the stage is moving up and down. Thereby, the time required for loading can be reduced, and the time required for preparation such as exposure can be shortened. In addition, since it is not necessary to load at high speed, vibration applied to the stage from the loader can be suppressed.

  The stage circulation device according to claim 2 is the stage circulation device according to claim 1, wherein the unloader lowers the load from the stage while the stage is moving up and down. .

  In the stage circulation apparatus according to claim 2, the unloader lowers the load from the stage while the stage is moving up and down. As a result, the time required for unloading can be reduced, and the time required for preparation such as exposure can be shortened. In addition, since it is not necessary to perform unloading at high speed, vibration applied to the stage from the unloader can be suppressed.

  The stage circulation device according to claim 3 is the stage circulation device according to claim 1 or 2, wherein a negative pressure is generated in the stage, and a negative pressure generating hole for adsorbing and fixing the mounted object to the stage. The loader includes a holding means for holding the load, an elevating means for supporting the holding means so as to be extendable and elevating the holding means along the hoistway of the stage, and a holding means. Support means for applying elastic force and elastically contracting when the loaded object is pressed against the stage to gradually increase the pressing force for pressing the loaded object against the stage, wherein the negative pressure generating hole is the mounted The speed at which the pressing force is increased to a value necessary for bringing an object into close contact with the stage is set to a control speed at which the amplitude of vibration generated in the stage by the pressing force can be suppressed to a limit value or less. To.

  In the stage circulation apparatus according to the third aspect, the elevating means elevates and lowers the holding means supported so as to extend and contract along the hoistway of the stage. The supporting means applies an elastic force to the holding means, and when the load held by the holding means is pressed against the stage, the support means gradually contracts and gradually increases the pressing force for pressing the load against the stage.

  Here, this pressing force is increased to a value necessary for the negative pressure generating hole to bring the load into close contact with the stage. The speed at which this pressing force is increased is the amplitude of vibration generated on the stage by the pressing force. Is controlled at a speed that can be suppressed below the limit value. This limit value is, for example, an amplitude of stage vibration that can allow an influence on the exposure process in the exposure apparatus.

  That is, it is possible to apply a pressing force necessary to bring the mounted object in close contact with the stage, and to suppress the vibration applied to the stage below an allowable amount.

  The stage circulation device according to claim 4 is the stage circulation device according to claim 3, wherein the loader decreases the pressing force from the required value after increasing the pressing force to the required value. The speed to perform is the control speed.

  5. The stage circulating apparatus according to claim 4, wherein the speed at which the loader reduces the pressing force from the required value after the load is attracted and fixed to the stage is a limit value of the amplitude of vibration generated on the stage by the pressing force. The control speed can be suppressed to the following. For this reason, when the loader stops pressing the load and the stage, the vibration applied to the stage can be reduced to an allowable amount or less.

  The stage circulating apparatus according to claim 5 is the stage circulating apparatus according to claim 3 or 4, wherein the holding force of the holding means is released when the mounted object is fixed to the stage. To do.

  In the stage circulation apparatus according to claim 5, since the holding force of the holding means is released when the mounted object is fixed to the stage by suction, the mounted object does not float from the stage when the holding means is separated from the stage. .

  An image forming apparatus according to a sixth aspect includes the stage circulation device according to any one of the first to fifth aspects, and forms an image on the mounted object mounted on the stage when the stage moves horizontally. An image forming unit is included.

  In the image forming apparatus according to the sixth aspect, when the stage moves horizontally, the image forming unit forms an image on a mounted object mounted on the stage. Since the stage circulating apparatus can shorten the time required for the preparation of the image forming process, a plurality of stages can be continuously sent to the image forming process.

  In addition, since the vibration applied to the stage is suppressed to an allowable amount or less, an image can be favorably formed on the mounted object.

  An image forming apparatus according to a seventh aspect is the image forming apparatus according to the sixth aspect, wherein the image forming means is a spatial modulation element.

  In the image forming apparatus according to the seventh aspect, the stage can be sent continuously to the image forming process by the spatial modulation element. In addition, since the vibration applied to the stage is suppressed to an allowable amount or less, an image can be favorably formed by the spatial modulation element.

  Since the present invention has the above-described configuration, the time required for exposure preparation can be shortened, and a necessary pressing force sufficient to bring the substrate into close contact with the stage can be applied to the mounted object and the stage, and further vibrations applied to the stage are allowed. It can be suppressed below the capacity.

  Embodiments of the present invention will be described below with reference to the drawings.

  1 and 2 are schematic perspective views showing a laser exposure apparatus 10 including a stage circulation device 11 of the present invention and an exposure head 100 as an image forming means. The laser exposure apparatus 10 according to the present invention exposes a thin plate-like substrate material 200, which is a material for a printed wiring board, with a laser beam B modulated by image information while conveying the substrate material 200 at a predetermined speed. In 200, an image (latent image) corresponding to the wiring pattern is formed.

  Therefore, for convenience of explanation, the direction represented by the arrow X in FIG. 1 is referred to as the “conveying direction” of the substrate material 200, and “upstream side” and “downstream side” are expressed based on this. Further, the direction opposite to that is defined as the “return direction” of the substrate material 200. Furthermore, a direction orthogonal to the arrow X is represented by an arrow Y and is defined as a “width direction” in the laser exposure apparatus 10.

[Outline of exposure apparatus]
First, an outline of the laser exposure apparatus 10 will be described. As shown in FIGS. 1 and 2, the laser exposure apparatus 10 is a substantially “L” -shaped stage member having a predetermined thickness and moving in the conveyance direction while adsorbing and holding the substrate material 200 on the surface (upper surface). Are provided. Although the two stage members 20 and 30 have the same configuration, for convenience of explanation, the left side in the transport direction is the stage member 20 and the right side is the stage member 30. In addition, the substrate material 200 may be described as the substrate material 200 </ b> A that is attracted and held on the stage member 20, and the substrate material 200 </ b> B that is attracted and held on the stage member 30.

  Each stage member 20 and 30 is cantilevered so as to be movable up and down by linear running bodies 40 and 60 as conveying means, respectively, and each linear running body 40 and 60 is adjacent so that stage members 20 and 30 come inside. Thus, it is supported so as to be movable in the transport direction and the return direction. Therefore, when the linear traveling bodies 40 and 60 pass each other, for example, one stage member 20 is moved up and down, and the other stage member 30 is moved down to prevent the inner stage members 20 and 30 from interfering with each other. I try to move it. That is, the stage members 20 and 30 move in the transport direction at the upper position, and the substrate material 200 sucked and held by the stage members 20 and 30 is exposed and removed, and then moved in the return direction at the lower position. Then, it returns to the original initial position (mounting position where the substrate material 200 is loaded).

  The linear traveling bodies 40 and 60 are movably supported on the base 12, and a pair of side walls 14 are erected on both sides of the base 12 in the transport direction. A gate 18 for mounting a CCD camera 182 (alignment camera) constituting the image position detection device 180 is installed in the width direction above the side wall 14. Further, a gate 16 for mounting a plurality of exposure heads 100 is installed in the width direction on the upper portion of the downstream side wall 14 spaced apart from the gate 18 by a predetermined distance.

  The exposure head 100 is fixed in a downward state so that the laser beam B can be irradiated toward the substrate material 200 passing through the gate 16, and the CCD camera 182 is positioned at the position of the substrate material 200 passing through the gate 18 ( (Drawing region) The alignment mark (not shown) for detection is provided in a downward state and reciprocally movable in the width direction so that it can be imaged.

  Therefore, the laser exposure apparatus 10 mainly operates as follows. First, the substrate material 200 </ b> A is placed on the placement surface 22 </ b> A of the stage member 20 by the loader 80. Then, while being conveyed while being sucked and held on the mounting surface 22A, the alignment mark is imaged by the CCD camera 182, and the position (drawing area) is detected. Further, based on the detection result, a predetermined value is detected. The drawing area is exposed by the exposure head 100. When the exposure is completed, the substrate material (printed wiring board) 200A is removed from the stage member 20 by the unloader 90.

  On the other hand, at this time, the stage member 30 is already transported in a state where the next substrate material 200B is sucked and held on the mounting surface 32A, and the position is detected by the CCD camera 182 and exposure is started. In other words, the stage member 30 on which the substrate material (printed wiring board) has been unloaded first passes below the stage member 20 while the substrate material 200A on the stage member 20 is exposed, and the initial position (mounting). It moves back to the position), and the next substrate material 200 </ b> B is loaded, and the process proceeds to a step where the position is detected by the CCD camera 182.

  As described above, the laser exposure apparatus 10 is configured such that the exposure of the substrate material 200 is sequentially performed continuously by each stage member 20 and 30 being circulated alternately, and the operating rate of the exposure head 100, that is, The production efficiency of the printed wiring board is improved.

  Here, in the laser exposure apparatus 10, the loader 80 loads the substrate material 200 on the stage members 20, 30 while the stage members 20, 30 are raised in the lifting section at the upstream end in the transport direction. The unloader 90 lowers the substrate material 200 from the stage members 20 and 30 while 30 is descending in the ascending / descending section at the downstream end portion in the transport direction. As a result, the time required for exposure preparation of the stage after the exposure process is shortened, and the manufacturing efficiency of the printed wiring board is further improved. Details will be described later.

  The above is the outline of the laser exposure apparatus 10, and the configuration of each unit will be described in detail below.

[Configuration of exposure head]
First, the configuration of the exposure head 100 will be described in detail with reference to FIGS. As described above, the exposure head 100 is suspended from the upper portion of the gate 16 laid in the width direction of the laser exposure apparatus 10, and the exposure position directly below the substrate is sucked and held by the stage member 20 and conveyed. When the material 200 passes, the exposed surface 202 of the substrate material 200 is exposed by irradiating a laser beam B modulated based on image information from above, and the exposed surface 202 is printed on a printed wiring board. An image (latent image) corresponding to the wiring pattern is formed.

  Here, the upper surface portion of the substrate material 200 is an exposed surface 202 on which a thin photosensitive coating film is formed by a photosensitive material, and the exposed surface 202 is etched after forming a latent image (image). By receiving this predetermined processing, a wiring pattern corresponding to the latent image is formed. The photosensitive coating film is formed by applying a liquid photosensitive material to the substrate material 200 and drying and curing it, or laminating a photosensitive material previously formed into a film shape.

As shown in FIGS. 6 and 7, the exposure head 100 is configured by arranging a plurality (for example, 14 pieces) of an approximate matrix of m rows and n columns (for example, 3 rows and 5 columns). In relation to the width of the substrate material 200, four exposure heads 100 are arranged in the third row. Hereinafter, when the individual exposure heads arranged in the m-th row and the n-th column are indicated, they are denoted as the exposure head 100 _mn .

An exposure area 102 by the exposure head 100 has a rectangular shape with a short side in the sub-scanning direction. Accordingly, when the stage member 20 moves in the transport direction (by moving the exposure head 100 relatively in the sub-scanning direction), the drawing region 204 on the exposed surface 202 of the substrate material 200 is provided for each exposure head 100. A strip-shaped exposed region 206 is sequentially formed. Hereinafter, when the exposure area 102 by the individual exposure heads 100 arranged in the m-th row and the n-th column is indicated, it is expressed as an exposure area 102 _mn .

Further, as shown in FIG. 7, the exposure heads 100 of each row arranged in a line are arranged so that the strip-shaped exposed regions 206 are arranged without gaps in a direction orthogonal to the sub-scanning direction (main scanning direction). They are arranged so as to be shifted in the direction by a predetermined interval (natural number times the long side of the exposure area, twice in this embodiment). Therefore, can not be exposed portion between the exposure area 102 ₁₁ in the first row and the exposure area 102 _12, it can be exposed by the second row of the exposure area 102 ₂₁ and the exposure area 102 ₃₁ in the third row.

As shown in FIG. 8, each of the exposure heads 100 _{11 to} 100 _mn is a digital micromirror device (hereinafter referred to as “a spatial light modulation device”) that modulates an incident light beam for each pixel in accordance with image information. DMD ”) 106. As shown in the figure, the DMD 106 includes a large number (for example, 600 × 800) of micromirrors (hereinafter referred to as “micromirrors”) 110 constituting a pixel (pixel) on a SRAM cell (memory cell) 108. The mirror device is integrally arranged in a shape, and a material having high reflectivity such as aluminum is deposited on the surface of the micromirror 110 so that the reflectivity is 90% or more. Each micromirror 110 is supported by a support (not shown) including a hinge and a yoke.

  Therefore, when a digital signal is written in the SRAM cell 108 of the DMD 106, the micromirror 110 supported by the support is within a range of ± α ° (for example, ± 10 °) with respect to the base side where the DMD 106 is disposed with the diagonal line as the center. Tilted at. That is, by controlling the tilt of the micromirror 110 of the DMD 106 according to the image signal, the light incident on the DMD 106 is reflected in the tilt direction of each micromirror 110. Incidentally, FIG. 9A shows a state where the micromirror 110 is tilted to + α ° when the micromirror 110 is in the ON state, and FIG. 9B shows a state where the micromirror 110 is tilted to −α ° when the micromirror 110 is in the OFF state. . A light absorber (not shown) is arranged in the direction in which the light beam is reflected by the micromirror 110 in the OFF state.

Further, as described above, the DMD 106 is configured by arranging a large number (for example, 800 sets) of micromirror arrays 110 in the longitudinal direction and arranging a large number of sets (for example, 600 sets) in the short direction. However, the side (short side) in the short direction is further slightly inclined so as to form a predetermined angle θ (for example, 1 ° to 5 °) with the sub-scanning direction. 10A shows the scanning trajectory of the reflected light image (exposure beam) 104 by each micromirror 110 when the DMD 106 is not tilted, and FIG. 10B shows the reflected light image when the DMD 106 is tilted by a predetermined angle θ. A scanning trajectory of (exposure beam) 104 is shown. Thus, when the DMD 106 is tilted, the pitch P ₂ of the scanning trajectory (scan line) of the exposure beam by each micromirror 110 can be made narrower than the pitch P ₁ of the scanning line when the DMD 106 is not tilted. The resolution can be greatly improved.

Furthermore, since the same scanning line is overlaid by different micromirror rows and exposed (multiple exposure), a very small amount of exposure position can be controlled, and high-definition exposure can be realized. Therefore, the joints between the plurality of exposure heads 100 arranged in the main scanning direction can be connected without a step by a very small exposure position control. Since the tilt angle θ of the DMD 106 is very small, the scan width W ₂ when the DMD 106 is tilted and the scan width W ₁ when the DMD 106 is not tilted are substantially the same. It goes without saying that the same effect can be obtained by arranging the micromirror rows in a staggered pattern shifted by a predetermined interval in a direction orthogonal to the sub-scanning direction instead of inclining the DMD 106.

  Further, an image information processing unit (not shown) and a mirror drive control unit (not shown) are incorporated in a control device (not shown) for driving and controlling the exposure head 100. In the image information processing unit, each micro-pixel within the region to be controlled by the DMD 106 is controlled for each exposure head 100 based on image information corresponding to a wiring pattern input from a controller (not shown) that controls the entire laser exposure apparatus 10. A control signal for driving and controlling the mirror 110 is generated. In the mirror drive control unit, the angle of each micro mirror 110 of the DMD 106 is controlled to be in an ON state or an OFF state for each exposure head 100 based on a control signal generated by the image information processing unit.

  Further, as shown in FIG. 11, on the light incident side of the DMD 106, a laser emitting portion in which the emitting end portion (light emitting point) of the optical fiber is arranged in a line along the direction corresponding to the long side direction of the exposure area 102. 114, a lens array 120 that corrects the laser light emitted from the fiber array light source 112 and collects the light on the DMD 106, and reflects the laser light transmitted through the lens system 120 toward the DMD 106. A mirror 116 is arranged in order. On the light reflection side of the DMD 106, lens systems 122 and 124 that form an image of the laser light reflected by the DMD 106 on the exposed surface 202 of the substrate material 200 have a conjugate relationship between the DMD 106 and the exposed surface 202. It is arranged to be.

  In the lens system 120, as shown in FIG. 12, a pair of combination lenses 126 that convert the laser light emitted from the fiber array light source 112 into parallel light and the light quantity distribution of the parallel laser light become uniform. A pair of combination lenses 128 that are corrected in this way, and a condensing lens 118 that condenses the laser light with the corrected light quantity distribution on the DMD 106. In the arrangement direction of the laser emitting end, the combination lens 128 spreads the light flux at a portion close to the optical axis of the lens, contracts the light flux at a portion away from the optical axis, and further in a direction perpendicular to the arrangement direction. On the other hand, it has a function of allowing light to pass through as it is, and corrects the laser light so that the light quantity distribution is uniform.

  As shown in FIG. 13A, the fiber array light source 112 includes a plurality of (for example, six) laser modules 130, and one end of a multimode optical fiber 132 is coupled to each laser module 130. Yes. An optical fiber 134 having the same core diameter as that of the multimode optical fiber 132 and a cladding diameter smaller than that of the multimode optical fiber 132 is coupled to the other end of the multimode optical fiber 132. As shown in FIG. The laser emission unit 114 is configured by arranging the emission end portions (light emission points) in one row along the main scanning direction orthogonal to the sub-scanning direction. As shown in FIG. 13D, it is also possible to arrange the emission end portions (light emission points) of the optical fibers 134 in two rows along the main scanning direction.

  As shown in FIG. 13B, the exit end of the optical fiber 134 is sandwiched and fixed between two support plates 136 having a flat surface. A transparent protective plate 138 such as glass is disposed on the light emitting side of the optical fiber 134 to protect the end face of the optical fiber 134. The protective plate 138 may be disposed in close contact with the end surface of the optical fiber 134 or may be disposed so that the end surface of the optical fiber 134 is sealed. The exit end of the optical fiber 134 has a high light density and is likely to collect dust and easily deteriorate. However, the protective plate 138 can prevent dust from adhering to the end face and delay deterioration. Can do.

  Further, as shown in FIG. 13B, in order to arrange the output ends of the optical fibers 134 having a small cladding diameter in a single row without any gaps, between the two multimode optical fibers 132 adjacent to each other at a portion having a large cladding diameter. The multi-mode optical fibers 132 are stacked, and the output ends of the optical fibers 134 coupled to the stacked multi-mode optical fibers 132 are coupled to the two multi-mode optical fibers 132 adjacent to each other at a portion where the clad diameter is large. They are arranged so as to be sandwiched between the emission ends. This is because an optical fiber 134 having a small cladding diameter of 1 to 30 cm is coaxially coupled to the tip portion of the multimode optical fiber 132 having a large cladding diameter on the laser light emission side. It can be obtained by fusing to the emission end face of the optical fiber 132 so that both central axes coincide.

  As the multimode optical fiber 132 and the optical fiber 134, any of a step index type optical fiber, a graded index type optical fiber, and a composite type optical fiber can be used. As shown in FIG. The diameter is the same as the diameter of the core 132 </ b> A of the multimode optical fiber 132. That is, the optical fiber 134 has a cladding diameter = 60 μm and a core diameter = 25 μm, and the multimode optical fiber 132 has a cladding diameter = 125 μm and a core diameter = 25 μm. The transmittance of the incident end surface coat of the multimode optical fiber 132 is 99.5% or more.

  Although not shown, a short optical fiber in which an optical fiber with a short cladding diameter and a large cladding diameter is fused with an optical fiber with a small cladding diameter is coupled to the output end of the multimode optical fiber 132 via a ferrule or an optical connector. May be. In this way, when a short optical fiber (optical fiber with a small cladding diameter) is configured to be detachable from the multi-mode optical fiber 132 using an optical connector or the like, if the optical fiber with a small cladding diameter is damaged, the portion is replaced. Therefore, the cost required for maintenance of the exposure head 100 can be reduced. Hereinafter, the optical fiber 134 may be referred to as an emission end portion of the multimode optical fiber 132.

  The laser module 130 includes a combined laser light source (fiber light source) shown in FIG. This combined laser light source includes a plurality of (for example, seven) chip-shaped lateral multimode or single mode UV semiconductor lasers LD1, LD2, LD3, LD4, LD5, LD6 arranged and fixed on the heat block 140, LD 7, collimator lenses 142, 144, 146, 148, 150, 152, 154, one condenser lens 156, and one multimode provided corresponding to each of the UV semiconductor lasers LD 1 to LD 7 An optical fiber 132 is included. That is, the collimator lenses 142 to 154 and the condenser lens 156 constitute a condensing optical system, and the condensing optical system and the multimode optical fiber 132 constitute a multiplexing optical system.

  Therefore, in the exposure head 100, the laser beams B1, B2, B3, B4, B5, B6, B7 emitted in a divergent light state from each of the UV semiconductor lasers LD1 to LD7 constituting the combined laser light source of the fiber array light source 112. Each is first collimated by corresponding collimator lenses 142-154. The collimated laser beams B <b> 1 to B <b> 7 are collected by the condenser lens 156 and converge on the incident end face of the core 132 </ b> A of the multimode optical fiber 132.

  The laser beams B1 to B7 converged on the incident end face of the core 132A of the multimode optical fiber 132 are incident on the core 132A, propagate through the optical fiber, and are combined into one laser beam B. The UV-based semiconductor lasers LD1 to LD7 all have the same oscillation wavelength and maximum output. If the coupling efficiency at this time is, for example, 85%, the outputs of the UV-based semiconductor lasers LD1 to LD7 are 30 mW. Can obtain a combined laser beam B with an output of about 180 mW (= 30 mW × 0.85 × 7).

  Thus, the combined laser beam B is emitted from the optical fiber 134 coupled to the emission end of the multimode optical fiber 132. For example, as shown in FIGS. 11 and 13C, the six optical fibers 134 are arranged in an array. In the case of the laser emitting units 114 arranged in a row (in which high-luminance light emitting points are arranged in a line along the main scanning direction), the output becomes a high output of about 1 W (= 180 mW × 6). The number of UV semiconductor lasers constituting the combined laser light source is not limited to seven.

  Further, the combined laser light source (UV semiconductor laser) as described above is housed in a box-shaped package 160 having an upper opening, together with other optical elements, as shown in FIGS. The package 160 includes a package lid 162 that can close the opening. After the degassing process, a sealing gas is injected, and the package 160 is closed with the package lid 162, whereby the package 160 and the package lid 162 are closed. The combined laser light source is hermetically sealed in a closed space (sealed space) formed by the above.

  A base plate 164 is fixed to the bottom surface of the package 160, and the heat block 140, the condensing lens holder 158 that holds the condensing lens 156, and the incident end of the multimode optical fiber 132 are disposed on the upper surface of the base plate 164. A fiber holder 166 for holding the part is attached. The exit end of the multimode optical fiber 132 is drawn out of the package 160 through an opening formed in the wall surface of the package 160.

  A collimator lens holder 168 is attached to the side surface of the heat block 140, and the collimator lenses 142 to 154 are held. An opening is formed in the lateral wall surface of the package 160, and wiring 170 for supplying a driving current to the UV semiconductor lasers LD <b> 1 to LD <b> 7 is drawn out of the package 160 through the opening. In FIGS. 16 and 17, in order to avoid complication of the drawings, only the UV semiconductor laser LD7 among the plurality of UV semiconductor lasers is provided with a reference numeral, and among the plurality of collimator lenses, the collimator is used. Only the lens 154 has a reference numeral.

  Moreover, the front shape of the attachment part of the collimator lenses 142-154 is shown in FIG. Each of the collimator lenses 142 to 154 is formed in a shape in which a region including the optical axis of a circular lens having an aspherical surface is cut out in a parallel plane. The elongated collimator lenses 142 to 154 can be obtained, for example, by molding resin or optical glass. The collimator lenses 142 to 154 are closely arranged in the arrangement direction of the light emitting points so that the length direction is orthogonal to the arrangement direction of the light emitting points of the UV semiconductor lasers LD1 to LD7 (left and right direction in the figure). Yes.

  The UV-based semiconductor lasers LD1 to LD7 each have an active layer with an emission width of 2 μm, and each laser beam has a divergence angle in a direction parallel to and perpendicular to the active layer, for example, 10 ° and 30 °. Lasers emitting B1 to B7 are used. These UV-based semiconductor lasers LD1 to LD7 are arranged so that the light emitting points are arranged in a line in a direction parallel to the active layer. Therefore, the laser beams B1 to B7 emitted from the respective light emitting points have a width direction in which the direction in which the divergence angle is large coincides with the length direction and the direction in which the divergence angle is small with respect to the elongated collimator lenses 142 to 154. Incident light is incident in a state that coincides with the direction (direction perpendicular to the length direction).

  In addition, the condenser lens 156 is obtained by cutting an area including the optical axis of a circular lens having an aspherical surface into a long and narrow plane parallel to the arrangement direction of the collimator lenses 142 to 154, that is, a direction that is long in the horizontal direction and perpendicular thereto. It is formed in a short shape. This condensing lens 156 can also be obtained, for example, by molding resin or optical glass.

[Configuration of Image Position Detection Device]
Next, the image position detection apparatus 180 will be described. As described above, the image position detection device 180 includes a CCD camera 182 that is attached to the gate 18 installed in the width direction of the laser exposure device 10 so as to be movable along the width direction, and an alignment control unit (not shown). ). The CCD camera 182 includes a two-dimensional CCD as an image sensor, and also includes a strobe as a light source at the time of imaging. The light receiving sensitivity of the element is set. The alignment control unit processes the image signal from the CCD camera 182 and outputs position information corresponding to the position of the alignment mark imaged by the CCD camera 182 to the controller.

  The CCD camera 182 is held downward by a holder 184, and this holder 184 is movably supported by a guide plate 186 disposed in parallel to the lower part of the gate 18. Therefore, the CCD camera 182 can reciprocate in the width direction along the guide plate 186 so that different areas of the substrate material 200 can be imaged. That is, the CCD camera 182 can be adjusted in position according to the position of the alignment mark formed on the substrate material 200 to be imaged. The number of CCD cameras 182 is not limited to the one shown in the figure, and a plurality of CCD cameras may be provided and fixed at appropriate positions.

  On the other hand, a drawing area 204 in which a latent image corresponding to the wiring pattern is formed in advance is set on the exposed surface 202 of the substrate material 200, and a plurality of alignment marks corresponding to the drawing area 204 are arranged in the transport direction. Are formed along. Then, the CCD camera 182 emits a strobe at a predetermined timing when the substrate material 200 that is attracted and held by the stage member 20 and conveyed at a predetermined speed passes through the imaging position (reading position) directly below the CCD camera 182. By receiving the reflected light of the light from the strobe, the imaging range including the alignment mark in the substrate material 200 is respectively imaged.

  The alignment mark is formed by providing a circular through-hole or recess in the exposed surface 202 of the substrate material 200, whereby the position (drawing region) of the substrate material 200 on the stage member 20 is detected. It is like that. The alignment mark may be a land that is a wiring pattern formed in advance on the exposed surface 202 of the substrate material 200 instead of the through-hole or the recess.

[Configuration of stage member and circulating means]
Next, the structure of the stage members 20 and 30 and the circulation means thereof will be described in detail with reference to FIGS. The stage members 20, 30 have stage bodies 22, 32 whose upper surfaces (surfaces) are planar mounting surfaces 22 A, 32 A for placing the substrate material 200, and the outer sides of the stage bodies 22, 32. With the guide walls 24 and 34 erected integrally at the end upward, the guide walls 24 and 34 are formed in a substantially “L” shape in a side view longer in the horizontal direction than in the vertical direction.

  A pair of rails 26 and 36 are formed at both ends of the outer surfaces of the guide walls 24 and 34. The pair of rails 26 and 36 are formed with guide grooves having a substantially inverted "concave" shape in cross section in the vertical direction and over the entire length. Yes. The stage bodies 22 and 32 are hollow inside, and a large number of air suction small holes 22B and 32B for adsorbing the substrate material 200 by negative pressure are formed on the mounting surfaces 22A and 32A. ing. Therefore, the stage members 20 and 30 are connected to a cable bear (not shown) provided with a power supply line or air piping for generating a negative pressure.

  That is, when the stage members 20 and 30 are equipped with a vacuum generator (not shown) such as a vacuum pump for air suction, a cable bear having a power supply line for driving the vacuum generator is obtained. Is not provided, the cable bear is provided with an air pipe connected to a vacuum generator (not shown) such as a vacuum pump installed separately. The cable bear is preferably formed of a flexible tube or the like so as to be able to follow the movement of the stage members 20 and 30, but the linear traveling bodies 40 and 60 that integrally support the stage members 20 and 30. Is only reciprocated in the transport direction and the return direction on the same plane, the mounting structure of the cable bear to the stage members 20 and 30 is simple, and there is no problem that the cable bear becomes entangled.

  The linear traveling bodies 40 and 60 are composed of bottom plates 42 and 62 and guide walls 44 and 64 which are integrally provided upward at the outer side end portions of the bottom plates 42 and 62, and are more vertical than the horizontal direction. It is formed in a substantially “L” shape in a side view with a long direction, and a pair of guide rails 46, 66 are projected along the vertical direction at the both ends of the inner surfaces of the guide walls 44, 64 over the entire length. ing. A guide groove is slidably fitted to the guide rails 46 and 66 so that the stage members 20 and 30 are cantilevered integrally with the linear traveling bodies 40 and 60.

  Ball screws 48 and 68 are arranged in parallel between the guide rails 46 and 66, and the ball screws 48 and 68 can be rotated forward and backward at one end (for example, the lower end) of the ball screws 48 and 68. A motor (not shown) is attached. On the other hand, between the rails 26 and 36 of the guide walls 24 and 34, cylindrical members 28 and 38 having screw threads inside are integrally projected along the vertical direction. The ball screws 48 and 68 are inserted into the screw 38. Therefore, when the motor is driven to rotate forward and backward, the guide walls 24 and 34, that is, the stage members 20 and 30 can be moved up and down along the guide rails 46 and 66 of the guide walls 44 and 64.

  In addition, rails 52 and 72 having guide grooves each having a substantially inverted “concave” shape in cross-section in the transport direction are integrally provided on the lower surface of the bottom plates 42 and 62 and in the vicinity of the four corners. The guide groove is slidably fitted to a pair of guide rails 54 and 74 projecting from the upper surface of the flat base 12 having a predetermined thickness. As shown in the drawing, the guide rails 54 and 74 are adjacent to a predetermined position on the base 12 and are arranged in parallel along the conveying direction (returning direction) and substantially along the entire length, respectively. Between the guide rails 54 and 74 (inside), ball screws 56 and 76 are arranged in parallel to each other by a predetermined length. Near both ends of the ball screws 56 and 76 are supported by a pair of support portions (not shown), and motors 50 and 70 capable of forward and reverse rotation are respectively provided at the upstream (or downstream) ends. It is attached.

  On the other hand, a cylindrical member (not shown) having a screw thread inside is protruded integrally along the conveying direction (return direction) at the substantially lower center of the bottom plates 42 and 62. The ball screws 56, 76 are inserted in a state where they are screwed together. Therefore, when the motors 50 and 70 are driven to rotate forward and backward, the linear traveling bodies 40 and 60 are moved along the guide rails 54 and 74 at a predetermined speed in the transport direction and the return direction (for example, 30 mm / s during exposure). It is possible to move so as to be separable (passable). The motors 50 and 70 are configured to be rotationally driven by a drive pulse signal output from a conveyance control unit (not shown), and the conveyance control unit is connected to the controller. Further, the means for causing the linear traveling bodies 40 and 60 to travel is not limited to the illustrated ball screws 56 and 76, and may be configured to travel by a linear motor or the like.

  Further, as shown in the drawing, the linear traveling bodies 40, 60 are moved in the transport direction and the return direction with the cantilevered stage members 20, 30 facing each other. The length of the main bodies 22 and 32 in the width direction is longer than the length of the bottom plates 42 and 62 in the width direction. 22 and 32 move within the same area). Therefore, when the linear traveling bodies 40 and 60 pass each other, the stage members 20 and 30 are shifted from the upper position and the lower position so that the stage main bodies 22 and 32 do not interfere with each other.

  That is, the stage members 20 and 30 have the substrate material 200 mounted on the mounting surfaces 22A and 32A when the alignment process by the CCD camera 182 and the exposure process by the exposure head 100 are performed. When moving in the transport direction and returning from the take-out position to the mounting position, the substrate material 200 is removed from the placement surfaces 22A and 32A, so that it moves in the return direction at the lower position. Thus, if each stage member 20 and 30 moves up and down and mutual interference is avoided, the width direction of the laser exposure apparatus 10 can be comprised compactly (installation space can be reduced). There are advantages.

  As described above, when the alignment processing by the CCD camera 182 is performed after the stage members 20 and 30 are moved upward, the substrate material 200 when the stage members 20 and 30 are raised is used. Can be corrected during measurement by the CCD camera 182. Therefore, alignment with respect to the drawing area 204 can be performed with high accuracy.

  Further, since the stage members 20 and 30 are moved upward and exposure processing is performed by the exposure head 100, depending on the thickness of the substrate material 200, the exposed surface 202 of the substrate material 200, the exposure head 100, and the like. It is possible to adjust the focal length. That is, regardless of the thickness of the substrate material 200, the amount of elevation of the stage members 20 and 30 can be adjusted so that the distance between the exposed surface 202 of the substrate material 200 and the exposure head 100 is constant. It is not necessary to adjust the focal length by changing the mounting height position of the exposure head 100 for each substrate material 200 having a different thickness. Moreover, since the stage members 20 and 30 always travel integrally with the linear traveling bodies 40 and 60, the movement is performed with high accuracy.

[Load and unload process]
As shown in FIG. 1, the loader 80 includes suction members 82 that suck four corners of the substrate material 200. The inside of this adsorption member (adsorption holding means) 82 is a cavity, and a vacuum pump (not shown) is connected to this inside. In addition, a large number of small holes (not shown) are formed on the suction surface of the suction member 82, and negative pressure is generated from these small holes.

  Further, the suction member 82 is supported by the lower end portion of an elevating device (elevating means) 83 supported by the guide plate 84 so as to be movable in the transport direction and the return direction. The guide plate 84 extends from the supply conveyor 86 to the initial position (mounting position) of the stage members 20 and 30. That is, the suction member 82 sucks and holds the substrate material 200 on the supply conveyor 86 and moves to the initial position.

  The lifting device 83 includes a lifting portion 83A that includes a bearing portion that is movably supported by the guide plate 84 and a shaft portion that is slidably supported by the bearing portion. A rectangular support plate 83B is attached to the lower end of the elevating part 83A. The telescopic shaft 83C is suspended from the four corners of the support plate 83B.

  As shown in FIGS. 19 and 20, the telescopic shaft 83C includes a bearing portion 83D having one end portion in the axial direction attached to the support plate 83B, and a shaft portion 83E slidably supported by the bearing portion 83D. It is configured. And the adsorption member 82 is attached to the lower end part of this axial part 83E.

  One end of the compression coil spring 85 (support means) is attached to the lower end of the bearing portion 83D, the other end is attached to the upper portion of the adsorption member 82, and the shaft portion 83E is inserted into the compression coil spring 85. That is, the adsorbing member 82 is supported by the bearing 83D by the compression coil spring 85 so as to be swingable.

  Further, as shown in FIG. 1, the unloader 90 is configured in substantially the same manner as the loader 80, and the laser exposure is performed by sucking and holding the substrate material 200 that has been exposed at the elevation position of the downstream end of the stage members 20 and 30 in the transport direction. Unload to the discharge conveyor 96 on the downstream side in the transport direction of the apparatus 10.

  Hereinafter, loading and unloading methods will be described.

  As shown in FIGS. 19 and 20, the loader 80 loads the substrate material 200 onto the stage members 20 and 30 while the stage members 20 and 30 are rising from the lower stage to the upper stage in the lifting section at the upstream end in the transport direction. To do. Here, the loader 80 presses the substrate material 200 against the stage members 20 and 30 in order to correct the warpage of the substrate material 200 and bring the substrate material 200 into close contact with the stage members 20 and 30.

  Further, as shown in FIG. 21, the unloader 90 transfers the substrate material 200 that has been exposed while the stage members 20 and 30 are descending from the upper stage to the lower stage in the lifting section at the downstream end in the transport direction. Unload from 30.

As shown in FIG. 21 (A), the unloader 90 is decreasing at a faster rate V _D 'than the lowering speed V _D of the stage member 20, 30 approach toward the stage member 20, 30 is lowered, As shown in FIG. 21B, the substrate material 200 on the stage members 20 and 30 is lifted while being sucked and held. At this time, when the suction member 82 comes into contact with the substrate material 200, the compression coil spring 85 contracts to absorb the pressing force applied to the substrate material 200 and the stage members 20, 30 from the suction member 82.

Here, in the unloading process, it is not necessary to press the substrate material 200 against the stage members 20 and 30 as in the loading process. Therefore, the lowering speed V _D ′ of the adsorption member 82 is set as low as possible. It is desirable to reduce the pressing force applied to the substrate material 200 and the stage members 20 and 30 from the adsorption member 82 by reducing the vibration generated in the stage members 20 and 30 by approaching V _D.

  In the loading process, the substrate material 200 must be pressed against the stage members 20 and 30 by the adsorption member 82 as described above, while the stage is applied by the pressing force applied to the substrate material 200 and the stage members 20 and 30 from the adsorption member 82. The vibration generated in the members 20 and 30 must be suppressed.

  Hereinafter, a method for driving the loader 80 and the stage members 20 and 30 in the loading process will be described.

  As shown in FIG. 19A, the loader 80 waits for the stage members 20 and 30 to return to the lift section at the lowest position in the liftable range while holding the substrate material 200. Here, the lift stroke of the loader 80 is the same length as the lift stroke of the stage members 20, 30, and the lowest part of the loadable range of the loader 80 is a position that does not interfere with the horizontally moving stage members 20, 30. Yes.

Then, as shown in FIG. 19B, when it is detected that the stage members 20 and 30 have returned to the lifting section, the stage members 20 and 30 are moved at the speed V _U and the loader 80 is moved at the speed V _U ′. Raise with. Here, V _U > V _U ′, and the stage members 20 and 30 gradually approach the loader 80.

  Then, as shown in FIG. 19C, the stage members 20 and 30 and the substrate material 200 come into contact with each other, and a pressing force F is applied from the loader 80 to the substrate material 200 and the stage members 20 and 30. Then, as shown in FIG. 19D, the escape mechanism is activated, and the compression coil spring 85 is elastically contracted to absorb the pressing force F. As a result, the pressing force applied from the loader 80 to the substrate material 200 and the stage members 20 and 30 gradually increases.

Then, the stage members 20 and 30 and the loader 80 are lifted at a speed V _U > V _U ′ as they are, and as shown in FIG. 20A, the pressing force F is a predetermined value F _MAX (the substrate material 200 is transferred to the stage member 20 , 30, the speed of the loader 80 and the stage members 20, 30 are equal to each other for a predetermined time (τ′−τ, see the graph of FIG. 22) (V _U = V _U In the meantime, the substrate material 200 is sucked from the small holes 22B and 32B of the mounting surfaces 22A and 32A of the stage members 20 and 30, and the substrate material 200 is adsorbed to the stage members 20 and 30.

Here, if the pressing force F is rapidly increased to the specified value F _MAX , a large vibration is applied from the substrate material 200 to the stage members 20 and 30. For this reason, it is necessary to determine the increasing speed V _F of the pressing force F. Hereinafter, a method for setting the increasing speed V _F will be described.

The increase speed V _F is V _F = KV (= (KX)) where K is the elastic coefficient of the compression coil spring 85 and V (= V _U −V _U ′) is the relative speed between the loader 80 and the stage members 20 and 30. ', X: contraction length of the compression coil spring 85).

The increase speed V _{F is set} to a speed at which the amplitude A _pp of the vibration generated in the stage members 20 and 30 by the pressing force F can be suppressed to the limit value A _pp ′ or less. Here, the limit value refers to the amplitude of vibration that can be tolerated even if it occurs. That is, even if the vibration of the limit value A _pp ′ propagates from the stage members 20 and 30 being loaded to the stage members 20 and 30 being exposed, there is almost no influence on the exposure process and is acceptable. In the present embodiment, the limit value A _pp ′ is about 1 μm.

The vibration amplitude A _pp is defined by the transient vibration calculation formula (1) by making the force applied to the substrate material 200 and the stage members 20 and 30 into a trapezoidal profile as shown in the graph of FIG. The
A _pp = (4F _MAX / K _s ωτ) {| sin (ωτ / 2) |} (1)
K _s : Elastic coefficient ω of the stage members 20 and 30: Natural frequency τ of the stage members 20 and 30: Time for raising the pressing force F to the specified value F _MAX (see graph of FIG. 22)
Here, as described above, F _MAX needs a force that can correct the warpage of the substrate material 200 and is a fixed value. K _S is designed to be as large as possible, but is a fixed value with a limit. Further, ω is a fixed value determined from the weights and elastic coefficients of the stage members 20 and 30 and the linear traveling bodies 40 and 60. Furthermore, τ is a control variable that can be changed by controlling the increasing speed V.

In the present embodiment, K _S = 1.7 × 10 ⁷ [N / m], ω = 530 [rad / s], and F _MAX = 60 [N], and the start-up time τ and vibration under these conditions The relationship with the amplitude A _pp is shown in the graph of FIG.

It can be seen from the graph of FIG. 23 that the vibration amplitude A _pp when τ = 0.05 [S] is reduced to about 10% of the vibration amplitude A _pp when τ = 0. It can also be seen that the vibration amplitude A _pp when τ = 0.05 [S] is smaller than 1 μm which is the limit value A _pp ′. That is, the lower limit value of the start-up time τ is τ = 0.05 [S], and the upper limit value of the total value K of the elastic coefficients K ′ of the four compression coil springs 85 is K = 60 N / mm (K ′ = 15 N / mm). In the present embodiment, a compression coil spring 85 having an elastic coefficient K ′ = 2 to 5 N / mm is used.

Here, the prescribed value F _MAX satisfies the equation (2).
F _MAX = KX _MAX = 60 × X _MAX = 60 (2)
X _MAX : contraction length of the compression coil spring 85 when the specified value F _MAX is applied to the substrate material 200 and the stage members 20 and 30, that is, after X _MAX = 1 mm and the substrate material 200 contacts the stage members 20 and 30 The stages 20 and 30 may be raised by 1 mm relative to the loader 80 during 0.05 [S]. Accordingly, the relative speed V is V = X / τ = 1 / 0.05 = 20 [mm / s], and the increasing speed V _F of the pressing force _F is V _F = KV = 60 × 20 = 1200 [N / s].

As a result, the substrate material 200 can be brought into close contact with the stage members 20 and 30, and the vibration amplitude A _pp of the stage members 20 and 30 can be reduced to the extent that there is no problem even when propagating to the stage members 20 and 30 being exposed.

When the substrate material 200 is adsorbed to the stage members 20 and 30 in this way, the vacuum adsorbing of the adsorbing member 82 of the loader 80 is released and the ascending speed V _U ′ of the loader 80 is released as shown in FIG. Is made faster than the rising speed V _U of the stage members 20 and 30 (V _U ′> V _U ), and the pressing force F applied to the substrate material 200 and the stage members 20 and 30 is gradually released.

Here, as shown in the graph of FIG. 22, the speed V _F 'is to reduce the pressing force F, the same speed and the speed V _F to increase the pressing force. That is, the speed V _F ′ is set so that the pressing force F becomes 0 after τ = 0.05 [S] has elapsed after the pressing force F starts to decrease.

  Therefore, the vibration applied to the stage members 20 and 30 by releasing the pressing force F can be reduced, and the occurrence of uneven exposure on the substrate material 200 can be prevented.

  As shown in FIG. 20C, the pressing force F = 0 when the compression coil spring 85 is fully extended, and then the loader 80 is detached from the stage members 20 and 30 as shown in FIG. Is done. Then, the stage members 20 and 30 are raised to the upper stage. This completes the exposure preparation.

  While the loader 80 loads the substrate material 200 onto the stages 20 and 30 while the stages 20 and 30 are raised, loading the substrate material 200 onto the stages 20 and 30 causes the stages 20 and 30 to descend. It may be done while you are.

  Further, while the unloader 90 unloads the substrate material 200 from the stages 20 and 30 while the stages 20 and 30 are lowered, the unloading of the substrate material 200 is performed while the stages 20 and 30 are raised. You may make it do.

[Operation of exposure apparatus]
Next, a series of operations in the laser exposure apparatus 10 having the above-described configuration will be described with reference mainly to FIG. 1, FIG. 4, and FIG. First, the substrate material 200 </ b> A sequentially supplied by the supply conveyor 86 is stopped and positioned by a stopper (not shown), and the four corners are adsorbed by the adsorbing member 82 of the loader 80. Then, the loader 80 places the substrate material 200 </ b> A on the placement surface 22 </ b> A of the stage member 20 that is moving up the lifting section from the supply conveyor 86.

  At this time, since a negative pressure is supplied to the stage member 20 by a vacuum pump or the like via a cable bear, air is sucked from a large number of small holes 22B drilled in the mounting surface 22A. 200A is fixed in close contact with the mounting surface 22A.

  In this way, when the substrate material 200A is sucked and held on the mounting surface 22A of the stage member 20 and held at the upper position, the motor 50 is driven by the drive pulse signal from the transport control unit and the ball screw 56 rotates. Then, the linear traveling body 40 moves along the guide rail 54 in the transport direction at a predetermined speed. First, the CCD camera 182 moved to a predetermined position according to the substrate size along the transport direction of the substrate material 200A. The provided alignment mark is imaged, and the position of the drawing region 204 of the substrate material 200A is detected.

  That is, when the alignment mark of the substrate material 200 </ b> A reaches the imaging position (reading position) of the CCD camera 182, a strobe is emitted, and the CCD camera 182 captures an imaging area including the alignment mark on the exposed surface 202. The imaging information obtained by the CCD camera 182 is output to the alignment control unit. The alignment control unit converts the imaging information into position information corresponding to the position along the scanning direction and the width direction of the alignment mark, and outputs this position information to the controller.

  The controller determines the position of the alignment mark provided corresponding to the drawing area 204 based on the position information of the alignment mark from the alignment control unit. From the position of the alignment mark, the scanning direction and the width direction of the drawing area 204 are determined. And a tilt amount with respect to the scanning direction of the drawing area 204 are determined. That is, the controller determines the position of the substrate material 200 </ b> A on the stage member 20, determines the position of each alignment mark on the substrate material 200 </ b> A based on the image information, and determines the drawing region 204.

  The controller calculates the exposure start timing for the drawing area 204 based on the position of the drawing area 204 along the scanning direction, and based on the position along the width direction of the drawing area 204 and the amount of inclination with respect to the scanning direction. Then, the conversion process is performed on the image information corresponding to the wiring pattern, and the converted image information is stored in the frame memory.

  Here, the contents of the conversion process include a coordinate conversion process for rotating the image information around the coordinate origin, and a coordinate conversion process for translating the image information along the coordinate axis corresponding to the width direction. Further, as necessary, the controller executes a conversion process for expanding or contracting the image information in correspondence with the expansion amount and the reduction amount along the width direction and the scanning direction of the drawing area 204.

  The image information after the conversion process and the position information of the drawing area 204 obtained in this way are associated with the stage member 20 and temporarily stored in the frame memory of the controller. After being sent to a transfer device (not shown) for transfer to the next process (from the exposure apparatus 10), it is erased from the frame memory. In this embodiment, the alignment processing time is 1 second.

  Now, the substrate material 200A on which the alignment mark has been imaged is supplied to the exposure position of the exposure head 100 suspended from the gate 16 as the stage member 20 (linear running body 40) further moves in the transport direction. . Then, while moving at a predetermined speed (for example, 30 mm / s), the drawing area 204 whose position is detected by the alignment control unit based on the imaging by the CCD camera 182 is exposed based on the image information corresponding to the wiring pattern, A latent image (image) such as a wiring pattern is formed in the drawing region 204 of the substrate material 200A. That is, when the substrate material 200A is moved in the transport direction together with the stage member 20, the exposure head 100 is relatively sub-scanned in the return direction, so that the substrate material 200A has a strip-shaped exposure for each exposure head 100. The completed region 206 (see FIGS. 6 and 7) is formed sequentially.

  Here, the exposure process will be specifically described. First, the controller determines the position of the substrate material 200A on the stage member 20, and based on the position information of the drawing area 204 stored in the frame memory, The timing at which the tip of the drawing area 204 reaches the exposure position is determined. Then, an exposure start signal is output to the image information processing unit 15 in synchronization with the timing when the leading end of the drawing area 204 reaches the exposure position. As a result, the image information processing unit 15 sequentially reads image information stored in the frame memory for each of a plurality of lines, and generates a control signal for each exposure head 100 based on the read image information. Then, the mirror drive control unit 17 controls each of the micromirrors 110 of the DMD 106 to be in an ON state or an OFF state for each exposure head 100 based on the generated control signal.

  Thus, when the micromirror 110 of the DMD 106 is ON / OFF controlled, laser light is irradiated from the fiber array light source 112 to the DMD 106 and reflected by the micromirror 110 in the ON state, and the lens system 122, 124 causes the substrate material. An image is formed on the exposed surface 202 of 200A. That is, the laser light emitted from the fiber array light source 112 is turned ON / OFF for each pixel, and the drawing area 204 of the substrate material 200A is exposed in a pixel unit (exposure area) that is substantially the same as the number of used pixels of the DMD 106. The image information referred to here is data representing the density of each pixel constituting the image by binary values (whether or not dots are recorded), and the exposure processing time by the exposure head 100 in this embodiment is 15 seconds. ing.

  On the other hand, the exposure of the stage member 30 is completed when the exposure process of the substrate material 200A on the stage member 20 is started and until the exposure process of the substrate material 200A on the stage member 20 is completed. I am doing.

  That is, when the exposure process is completed, the stage member 30 descends to the lowest position in the lifting section at the downstream end in the transport direction, and the substrate material 200B is unloaded by the unloader 90 during this time. Then, the motor 70 rotates and drives the ball screw 56 in the direction opposite to that during conveyance, so that the stage member 30 moves horizontally to the elevation section at the upstream end in the conveyance direction at the lowest position. And it rises to the top. During this time, the substrate material 200B is placed on the placement surface 32A by the loader 80. At this time, the substrate material 200 </ b> B is sucked and held on the placement surface 32 </ b> A by a negative pressure action due to air being sucked from the small holes 32 </ b> B of the stage member 30.

  Thus, when the substrate material 200B is mounted and the stage member 30 is raised to the uppermost position, the motor 70 is driven by the drive pulse signal from the transfer control unit, and the ball screw 76 is rotated. Then, the linear traveling body 60 moves along the guide rail in the transport direction at a predetermined speed, and the alignment marks provided at the four corners of the substrate material 200B are imaged by the CCD camera 182 attached to the gate 18, and the substrate material The position of the drawing area 204 of 200B is detected. That is, the exposure preparation of the stage member 30 is completed in 15 seconds from the start of exposure of the stage member 20 to the end.

  On the other hand, when the exposure of the substrate material 200A is completed, the stage member 20 is lowered to a lower position in the lifting section at the downstream end in the transport direction. During this time, the negative pressure by the vacuum pump or the like of the stage member 20 is released, and the substrate material (printed wiring board) 200A is taken out from the placement surface 22A of the stage member 20 by the unloader 90. That is, the four corners of the substrate material 200 </ b> A are sucked by the suction member 82 of the unloader 90 and are transported along the guide plate 94 from the stage member 20 onto the discharge conveyor 96. Then, the substrate material (printed wiring board) 200A is transported to the next process by a transport device (not shown).

  The stage member 20 (linear traveling body 40) from which the substrate material 200A has been removed returns to the original initial position (mounting position) when the motor 50 rotates the ball screw 56 in the direction opposite to that during conveyance. Moving. Then, the above operation is repeated, and the stage member 30 on which the alignment processing of the substrate material 200B is performed also repeats the above operation after the exposure processing.

  As described above, in the above embodiment, loading and unloading are performed without stopping the stage members 20 and 30, so that the time required for exposure preparation can be shortened. In the configuration of the stage circulation device 11 of the present embodiment, when loading and unloading are not performed simultaneously with the raising and lowering of the stage members 20 and 30, the time required for exposure preparation is 19 seconds as shown in the table of FIG. However, by performing loading and unloading simultaneously with the raising and lowering of the stage members 20 and 30, the time required for exposure preparation is shortened to 14 seconds.

  Here, since the time required for exposure is 15 seconds, the exposure preparation of the other stage can be completed before the exposure of one stage is completed. That is, since the exposure of the other stage can be started at the same time as the exposure of one stage is completed, the speed of continuous exposure can be increased.

  In the above embodiment, the stage circulating apparatus according to the present invention has been described by taking the laser exposure apparatus 10 including the stage circulating apparatus 11 as an example. However, the stage circulating apparatus is not limited to this, and the stage is circulated at high speed. Applicable to devices that need it. In addition, as an example of an image forming apparatus including the stage circulation device according to the present invention, the laser exposure apparatus 10 that exposes the substrate material 200 that is a material of the printed wiring board has been described. However, the image forming apparatus according to the present invention includes: The present invention is not limited to the laser exposure apparatus 10 that exposes the substrate material 200, but can also be applied to photosensitive printing plates such as PS plates and CT printing plates, and exposure devices that expose photosensitive materials such as photosensitive paper.

  Further, the present invention is not limited to the laser exposure apparatus 10 that performs digital exposure, but can also be applied to a laser exposure apparatus that performs mask exposure. In addition to the laser beam, visible light, X-rays, or the like can be used as the light beam for exposing these. Furthermore, the image forming apparatus according to the present invention can be applied to an inkjet image forming apparatus and a display manufacturing apparatus.

It is a schematic perspective view which shows the laser exposure apparatus of this embodiment, a loader, and an unloader. It is a schematic perspective view which shows the structure of the laser exposure apparatus of this embodiment. It is a principal part schematic front view which shows the structure of the laser exposure apparatus of this embodiment. It is a schematic diagram which shows the process of the laser exposure apparatus of this embodiment. It is explanatory drawing which shows the tact of the laser exposure apparatus of this embodiment. It is a schematic perspective view which shows an exposure head. (A) is explanatory drawing which shows the exposed area | region formed in a substrate material, (B) is explanatory drawing which shows the arrangement | sequence of the exposure area by an exposure head. It is the elements on larger scale which show the structure of a digital micromirror device (DMD). (A) is explanatory drawing for demonstrating operation | movement of DMD, (B) is explanatory drawing for demonstrating operation | movement of DMD. (A) is a schematic plan view showing the scanning line of the exposure beam when the DMD is not tilted, and (B) is a schematic plan view showing the scanning line of the exposure beam when the DMD is tilted. It is a schematic perspective view which shows the structure of an exposure head. (A) is a schematic sectional drawing of the subscanning direction along the optical axis which shows the structure of an exposure head, (B) is a schematic side view of (A). (A) is a schematic perspective view showing the configuration of the fiber array light source, (B) is a partially enlarged view of (A), (C) is an explanatory view showing the arrangement of light emitting points in the laser emission part, and (D) is laser emission. It is explanatory drawing which shows the arrangement | sequence of the light emission point in a part. It is explanatory drawing which shows the structure of a multimode optical fiber. It is a schematic plan view which shows the structure of a multiplex laser light source. It is a schematic plan view which shows the structure of a laser module. It is a schematic side view which shows the structure of a laser module. It is a schematic front view which shows the structure of a laser module. (A)-(D) are schematic side views which show the loading method of a stage circulation apparatus. (A)-(D) are schematic side views which show the loading method of a stage circulation apparatus. (A), (B) is a schematic side view which shows the unloading method of a stage circulation apparatus. It is a graph which shows the increase in the pressing force of the loader of a stage circulation apparatus. It is a graph which shows the correlation of the raising time of the pressing force of the loader of a stage circulation apparatus, and the vibration which generate | occur | produces on a stage. It is the table | surface which put together the time which each process of the laser exposure apparatus of this embodiment requires.

Explanation of symbols

10 Laser exposure equipment (image forming equipment)
11 Stage circulation device 20, 30 Stage member (stage)
22B, 32B Small hole (negative pressure generating hole)
80 Loader 82 Adsorption member (Adsorption holding means)
83 Lifting device (lifting means)
85 Compression coil spring (support means)
90 Unloader 100 Exposure head (image forming means)
106 DMD (Spatial Modulation Element)
200 Substrate material (mounting)

Claims (7)

A stage circulating device in which a plurality of stages on which a load is mounted by a loader and the load is lowered by an unloader is moved up and down to change the height and horizontally move and circulate at a height that can pass each other,
The stage loader, wherein the loader mounts the load on the stage while the stage is moving up and down.   The stage unloader according to claim 1, wherein the unloader lowers the load from the stage while the stage is raised and lowered. The stage is formed with a negative pressure generating hole for generating a negative pressure and adsorbing and fixing the load on the stage,
The loader is
Holding means for holding the load;
Elevating means for supporting the holding means in a telescopic manner and elevating the holding means along a hoistway of the stage;
A support means for applying an elastic force to the holding means and gradually increasing a pressing force for pressing the load against the stage by elastic contraction when the load is pressed against the stage;
Control in which the negative pressure generating hole can suppress the speed at which the pressing force is increased to a value necessary for bringing the mounted object in close contact with the stage, and the amplitude of vibration generated in the stage by the pressing force can be suppressed to a limit value or less. The stage circulating apparatus according to claim 1 or 2, wherein a speed is set.   The stage loader according to claim 3, wherein the loader sets the control speed to a speed at which the pressing force is reduced from the required value after increasing the pressing force to the required value.   The stage circulating apparatus according to claim 3 or 4, wherein when the mounted object is fixed to the stage, the holding force of the holding means is released. The stage circulating apparatus according to any one of claims 1 to 5,
An image forming apparatus comprising image forming means for forming an image on the mounted object mounted on the stage when the stage moves horizontally.   The image forming apparatus according to claim 6, wherein the image forming unit is a spatial modulation element.

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